Insulation for Suspended Timber Floors

2020 SGIUK Ground floor Suspended Timber 2B_Floors_SuspendedTimber
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All ground floor constructions, unless very large commercial floors, will require some insulation to be included within the floor zone to comply with Building Regulation requirements. If the ground floor in question is of a suspended timber construction, and whether this is a renovation or new-build project, then the insulation would normally be installed in the joist zone – that is installed between the joists.

Glass mineral wool (GMW) roll or slab can be installed between the joists – the flexible nature of this type of product means it can be cut slightly oversize and then compression-fitted between the joists to eliminate air gaps. Some support may be needed for the insulation - timber straps, timber battens or netting can all be utilised to help keep the insulation in place. The floor would typically be finished from above with a vapour control layer (VCL) if required and a suitable timber floor deck.

Key Considerations

When using Isover products, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions. In addition to the product datasheet, please refer to the following product documents:

The building detail is for illustrative purposes only. It does not constitute advice and should not be relied upon.

Insulation products
Product Name Thickness Range Sizes Lambda
Isover Spacesaver 100-200mm Width 1.16m, Length 5.2 - 12.18m 0.044
Isover Spacesaver Lite 100-200mm Width 1.16m, Length 3.5 - 7m 0.044
Isover Spacesaver Plus 100-200mm Width 1.16mm, Length 3.5 – 7m 0.040
Isover Spacesaver Ready-Cut 100-200mm Width 3 x 0.386m or 2 x 5.8m, Length 5.2 - 12.18m 0.044